Don't take case in count when sorting non-ordered vector flag

Fixes: https://gitlab.cri.epita.fr/ing/majeures/srs/fic/server/-/issues/30

admin/sync/exercice_keys.go

@@ -67,7 +67,10 @@ func getRawKey(input interface{}, validatorRe string, ordered bool, showLines bo
 
 		ignord := "f"
 		if !ordered {
-			sort.Strings(fitems)
+			// Sort the list without taking the case in count.
+			sort.Slice(fitems, func(i, j int) bool {
+				return strings.ToLower(fitems[i]) < strings.ToLower(fitems[j])
+			})
 			ignord = "t"
 		}